基于DNA双链增强量子点自组装膜能量转移的界面比率传感

Interfacial Ratio Sensing Based on DNA Double Helix Enhancing Energy Transfer in Quantum Dots Self-Assembled Multilayers

分别以巯基乙酸（TGA）和三聚磷酸钠（STPP）为稳定剂，在水相条件下制备CdTe量子点和ZnO@CdS量子点．基于DNA双链增强自组装膜能量转移的原理，以ZnO@CdS量子点为能量供体，（kiTe量子点为能量受体，构筑Quartz／PDDA／CdTe／PDDA／T1一DNA／PDDA／Zn0@CdSSAMs自组装膜，并实现对DNA的界面比率传感．随着匹配DNA（P--DNA）的加入，ZnO@CdS量子点的荧光强度Fn减小，相对荧光强度FA／FD和P·-DNA浓度的负对数呈线性关系，线性范围为8．686×10。～6．080×10-8mol·L-1，检测限为0．707nmol·L-1．

CdTe quantum dots（QDs） and ZnO@CdS QDs were synthesized directly in aqueous solution which were re- spectively stabilized by thioglycolie acid and sodium tripolyphosphate. With ZnO@CdS quantum dots as energy donors and CdTe quantum dots as energy aceeptor, Quartz/PDDA/CdTe/PDDA/TI-DNA/PDDA/ZnO@CdS SAMs was con- structed and detected DNA by inferfaeial ratio sensing successfully based on DNA double helix enhaneing energy transfer of quantum dots self-assembled muhilayers. With the matching DNA （P1-DNA） adding, the fluorescence intensity of ZnO @CdS QDs decreased and CdTe QDs increased. A good linear relationship between the relative fluorescence intensity FA/ FD and the negative logarithm of concentration of P1-DNA could be obtained in the range from 8. 686 〉（ 10-9 to 6. 080 ）〈 10-8 tool L-1 and the detection limit was 0. 707 nmol L-1.